"If the situation reaches full separation and (regional) partition, this means the end of Lebanon as a state that has this model of peaceful cohabitation between religions and ethnicities," Saud told al-Arabiya Wednesday.
Faisal made the comment from Sharm el-Sheik where he attended preparatory meetings ahead of the Arab Economic Summit, the network said.
Saudi King Abdallah and Syrian President Bashar Assad had sought to mediate the situation in Lebanon following the collapse of the government last week.
Lebanon's political crisis erupted after 11 ministers affiliated with Hezbollah resigned from the government in response to an international tribunal investigating the 2005 assassination of former Prime Minister Rafik Hariri that indicted several Hezbollah members. Hezbollah had demanded current Prime Minister Saad Hariri denounce the tribunal, a request Hariri refused.